Corrosion-Resistant Membrane Condenser for Fuel Cell Exhaust
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fuel cell power plants face challenges in recovering water vapor from exhaust streams while preventing contamination by corrosive electrolytes, which can shorten system life and require costly replacements.
Innovation Solution
A corrosion-resistant membrane condenser system that separates and recovers water vapor and electrolyte vapor from fuel cell exhaust streams, using ceramic materials to prevent electrolyte contamination and extend condenser lifespan.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If water vapor is recovered from the cathode exhaust stream, then water can be recycled for humidifying and cooling purposes, but electrolyte vapor is also recovered which contaminates the water and makes it unusable for steam reforming
Solution Approach 1:
The condenser is divided into multiple channels with different functions: some channels condense water vapor while others condense electrolyte vapor. This segmentation allows separate recovery of water and electrolyte, preventing contamination of the recovered water while still capturing both vapors from the exhaust stream.
Solution Approach 2:
The patent uses a demister pad as an intermediary component between the condenser channels and the water recovery system. The demister pad removes electrolyte droplets from the condensed water, acting as a filtering mediator that allows water to pass through while trapping electrolyte contaminants.
2Loss of substance
If conventional condensers are used to recover water vapor, then water recovery is achieved, but the condenser components become corrosive due to electrolyte accumulation, shortening system life
Solution Approach 1:
The patent extracts electrolyte vapor from the exhaust stream in separate condenser channels before the condensed water reaches the recovery system. By removing the harmful electrolyte component first, the remaining water is free from corrosive contaminants that would otherwise damage the condenser and reduce its lifespan.
Solution Approach 2:
The system separately recovers and discards (or redirects) electrolyte vapor through dedicated channels, preventing it from contaminating the water recovery stream. This selective recovery and disposal approach protects the condenser components from corrosive damage while maintaining water recovery efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system efficiently recovers pure water for recycling and separates electrolyte vapor for proper disposal or re-injection, reducing maintenance costs and extending system life by using corrosion-resistant materials.
Implementation Method 1
Electrolyte vapor is condensed on the first side, water vapor is condensed inside the membrane
Data Source
AI summary
A system and method for recovering and separating water vapor and electrolyte vapor from an exhaust stream (22) of a fuel cell uses a membrane tube (72) comprising membrane (74) having an outer wall (76) and an inner wall (78), wherein exhaust stream (22) is directed to contact outer wall (76), electrolyte vapor is condensed on outer wall (76), and water vapor is condensed inside the membrane (74), the condensed water drawn from the membrane (74) to inner wall (78), leaving behind condensed electrolyte (88) on outer wall (76).